Stilbene disulfonic acid products



Patented a. 24, 1950 2,527,425

UNITED STATES PATENT OFFICE STILBENE DISULFONIC ACID PRODUCTS Ernst Keller and Reinhard Zweidler, Basel, Switzerland, assignors to J. R. Geigy- A. G., Basel, Switzerland, a Swiss firm No Drawing. Application October 18, 1948, Serial No. 55,233. In Switzerland October 31, 1947 4 Claims.

The present invention is concerned with the manufacture of brightening agents for animal and vegetable fibres having a more or less white: to faintly yellowish appearance. The new brightening agents or optical bleaching. agents that 4,4-diaminostilbene derivatives ofthe genare particularly suitable for adding to washing eral formula agents and rinsing liquors for vegetable fibres v and have better properties than bleaching agents Y-NH-0H=0H NH-CQ-X-R known so far, as hereinafter explained. I

Compounds belonging to the most varied S aH' SotH chemical types have already been suggested for wherein use as optical bleaching agents, including, among others, derivatives of 4,4-diaminostilbene some i i dlrecg carbon a -g dwalent of which have attained considerable importance. i f o formula" Thus by reacting 4,4-diaminostilbene-2,2-di- R g gi 1 v 1 sulphonic acid with 2 mole of cyanuric halide f i 5 0 owel ary Oxy and replacing the remaining halogen atoms by R y acl i 1 1 h be amino radicals, optical bleaching agents are 010- i yl g i a can tained distinguished by a blue fluorescence and s .g eXc u owever pronounced substantive character which makes 6 Su p omc am group them very suitable for brightening cellulose are distinguished by having good solubility in fibres. Still more valuable products are obwater, good affinity for the fibre, blue to greentained from the condensation'products named ish-blue fluorescence, better fastness to light above by treatment with formaldehyde. While and moderately good wet-fastness properties, so these agents are very well suited for the finish- 25 that they are suitable for brightening wool as ing of bleached material made from cellulose well as cellulose fibres and are excellent for mixfibres their use as additives to washing agents tures of both. Material brightened with these for ordinary domestic laundering and to rinsingagents has a very fine white appearance and q s has t tag t they aocumugood wet-fastness properties towards careful late on the fibre because of their pronounced 3O soap-washing. However, they can be removed substantivity and wet-fastness. Consequently, from the fibre to a large extent by a boiling soapafter repeated treatment the material acquires Wash so that there is no danger of an unwished an unpleasant violet to blue appearance owing for accumulation on the fibre after repeated use. to the very strong fluorescence of these com Consequently they are particularly suitable for pounds. Furthermore, they are little suited for 35 adding to washing agents for domestic laundertreating wool, because of too low affinity. 'Suiting and to rinsing liquors for white washing, able brightening agents for W001 fibres are di especially since they also have good stability toacylated 4,4-diaminostilbene-2,2-disulphonic wards salts of inorganic peracids. acids, for example, the diacetyl derivative, but The new brightening agents are obtained this has the disadvantage of a reddish fiuoreseither from a 4,4-diaminostilbene-disulphonio cence and too small anafiinity for cellulose acid monoacylated with an aryloxy fatty acid fibres. Again, the dibenzoyl or di-(p-aminobenradical by further acylation with an acylating zoyl) derivatives although having affinity for the agent introducing the RX-CO radical or cellulose; fibre also have unfortunately, a very from a 4,4"-diaminostilbene-disulphonic acid poor solubility in water and bad light-fastness, monoacylated by the RX-CO- radical by especially the second derivative named. They further acylation with a reactive derivative of readily precipitate from the liquor in which they an aryloxy fatty acid. The monoacylated 4,4- are being used, causing a pronounced spotty diaminostilbene compounds of the invention are white effect. Finally, the use .of 4,4-di-pheneasily available by reduction of the nitro group ylureido-stilbene-2,2-disu1phonic Y acids has of the corresponding 4-nitro-4'-acylaminostilq bene compounds. As reactive derivatives of aryloxy fatty acids, whereby only the lower members are considered, there come into consideration, for example, their anhydrides or acid halides. Special mention should be made of the phenoxyacetyl and cresoxyacetyl derivatives, which are particularly suitable. As acylating agents for introducing the R.XCO radical there come into consideration:

(a) when- X means a direct carbon linkage: anhydrides of lower fatty acids, such as, e. g., acetic anhydride and propionic anhydride or halides of these fatty acids such as, e. g., acetyl chloride, [l-bromopropionyl chloride, butyryl chloride and iso-butyryl chloride; anhydrides or halides of aryl-substituted fatty acids, e. g., phenylacetyl chloride; arylcarboxylic acid halides, e. g., benzoyl chloride, p-chlorobenzoyl chloride, 2-naphthoyl chloride and .l-naphthoyl chloride; E} i (b) when X means oxygen: chloroformic acid esters, e. g., methyl, ethyl, isopropyl and phenylchloroformate;

() when X means the NH-group: aliphatic isocyanates, e. g., methylisocyanate or aromatic isocyanates, e. g., phenyl isocyanate, p-chlorophenyl isocyanate, p-nitrophenyl isocyanate, naphthyl isocyanatej V (d) when X means the -a1kyleneO group: alkoxy fatty acid anhydrides or halides, e. g., methoxyacetic anhydride, ethoxyacetic anhydride and butoxyacetyl chloride or aryloxy fatty acid halides or anhydrides, e. g., phenoxyacetic anhydride, phenoxyacetyl chloride, chlorophenyloxyacetyl chloride, naphthyl-Z-oxyacetyl chloride, naphthyl-l-oxyacetyl chloride, chloronaphthyloxyacetyl chloride, a-phenoxy-pr'opionyl chloride and ,B-phenoxypropionyl chloride, whereby, as already mentioned hereinbefore, phenyloxy derivatives of lower fatty acids are considered of particular value.

It is self-evident that if Y is identical with R--X-CO- then the monoacyl compound of the 4,4-diaminostilbene derivative need not be specially prepared, since the latter compound can be twice acylated directly. Acylation can be carried out in an aqueous medium, or with good agita: tion, in a two phase system, for example, in a benzene-water mixture. In some cases it is advantageous to add an acid-binding agent, such as sodium acetate, sodium carbonate, calcium and magnesium carbonate or magnesium oxide.

When during the preparation of the new compounds radicals containing nitro groups are introduced on acylation with an aroyl-ating agent, such nitro groups can be reduced if desired and the resulting amino groups then acylated.

The new brightening agents are characterised by containing at least one aryloxy fatty acidacyl radical, while the second acyl group can be either the same as the first or greatly different. Besides the di-aryloxyacyl compounds, which are made particularly suitable by their beautiful greenish-blue fluorescence, those of the new compounds which contain an arylureido or urethane group as well as an aryloxyacylamino radical are especially valuable, since they are distinguished by possessing a beautiful blue fluorescence, good fastness to light and good drawing power on wool as well as on cellulose. a

The new bleaching agents are lpale yellow powders, soluble in water. soluble salts they can be mixed dry with any desired washing agent, or an aqueous solution, containing also the components 01 the washing In the form of their 4 agent, can be made into a powder ready for use either by evaporation and milling or by spraydrying.

The following examples further illustrate and explain the manufacture and use of the new optical bleaching agents, without restricting the invention in any way. Parts are by weight, unless otherwise stated, and the temperatures in degrees Centigrade.

Example 1 3'? parts of 4,4-diaminostilbene-2,2'-disulphonic acid are made into a neutral solution with 2000 parts of water and added in the presence of sodium acetate while stirring rapidly, to 42 parts of phenoxyacetyl chloride, dissolved in 250 parts of benzene. It is advantageous to neutralise the reaction mixture towards the end of the reaction by the addition of sodium carbonate or of caustic soda solution. On completion of acylation the reaction product is salted out and isolated. If necessary, it is dissolved in water and purified by treatment with such agents as will absorb or destroy any impurities present. When dried the sodium salt of 4,4-diphenoxyacetaminostilbene-2,2'-disulphonic acid is a white powder. It is soluble in water and can be used in aqueous solution, with the addition of Glaubers salt, for brightening cellulose fibres such as cotton, staple fibre, linen and the like. Wool is also distinctly brightened when treated in a weakly acid bath. The brightened fibres have good fastness to light, acid and alkali. However, the wet-fastness properties on cellulose are usually very moderate so that it is always possible to remove the brightening agent, e. g., by normal domestic laundering.

Example 2 40 parts of 4-nitro-4'-aminostilbene-2,2'-disulphonic acid are acylated with 21 parts of phenoxyacetyl chloride, with the addition of an acid binding agent such as sodium acetate, preferably in a bezene-water mixture. The nitro compound is then reduced, e. g., with iron and hydrochloric acid by the Bchamp method, to give 4-amino-4'-phenoxyacetaminostilbene-2,2- disulphonic acid. 51.4 parts of this amino compound are dissolved in 2000 parts of water, weakly acidified with acetic acid, and allowed to react, while stirring well, with 14.3 parts of phenyl isocyanate in 250 parts of benzene. The reaction product obtained is dissolved in hot water, filtered off from the small amount of diphenylurea formed as a by-product and, if necessary, further purified as explained in Example 1.

It is of course also possible to prepare 4 phenylureido 4 phenoxyacetaminostilbene 2,2 disulphonic acid by first treating 4-nitro- 4-aminostilbene-2,2-disulphonic acid with phenylisocyanate, then reducing and finally acylating with phenoxyacetyl chloride.

The sodium salt of the new compound is a white powder. It gives a very good brightening effect on cellulose fibres, with very good fastness to water, acid and light as well as a very fine shade which appears more bluish than that of the product described in Example 1. Since the product has only moderate fastness to washing, although possessing very good substantivity, it can be removed again by suitably strong laundering. At the same time it is distinguished by good fastness to perborate and is very suitable for addition to household Washing a ents or as a rinsing agent. It may also be used for brightening wool from a weakly acid bath and here again ..it shows algood lightening effect.

Example 3 51.4 parts of l-aminol'-phenoxyacetaminostilbene-2,2'-disulphonic acid prepared, e. g., as in Example 2 are treated in aqueous benzene solution with 26 parts of p-nitrophenoxyacetyl chloride. After the reaction is over the nitro compound is isolated and reduced with iron and hydrochloric acid to give 4'-(4-aminophenoxyacetamino) 4 phenoxyacetaminostilbene 2,2'-disulphonic acid.

66.3 parts of this amino compound are treated again preferably in a two-phase system, with 13.1 parts of ethyl chloroformate, the product separated and purified as required. It is a yellowish powder and can be used in aqueous solution for brightening textile fibres such as W001, cotton and staple fibre. On wool the efiects obtained have very good fastness to light and washing as well as good fastness to acid and alkali. Because of its properties on cellulose fibres the product is very suitable as an additive for washing agents.

Instead of with 26 parts of p-nitrophenoxyacetyl chloride, 51.4 parts of 4-amino-4'-phenoxyacetaminostilbene2,2'-disulphonic acid may be reacted with 20 parts of p-toluyl chloride in the two-phase system. The product thus obtained is an excellent brightening agent with very good fastness properties.

Example 4 tained allowed to react with a benzene solution of 21 parts of phenoxyacetyl'chloride. 'The purified product is a pale yellowish powder with useful brightening effects on wool and cellulose fibres. On wool in particular the wet-fastness properties and fastness to alkalis are very good.

Example 5 40 parts of 4,4-nitroaminostilbene-2,2'-disul- .the equivalent amount of methyl or .isopropyl chloroformate is used. These compounds may also be. built .up in .the reverse order by first.re..-..

acting 4,4-nitroaminostilbene-2,2' .d-isulphonic acid with the ester of chloreformic acid, reducing the urethane obtained to the amino-compound and then acylating with phenoxyacetyl chloride.

Example 7 51.4 parts of 4-amino-4'-phenoxyacetaminostilbene-2,2'-disulphonic acid are allowed to react in aqueous benzene solution with 23 parts of the ethyl ester of phenylisocyanate-m-carboxylic V formate. The product has a strong brightening Example 8 40 parts of 4,4-nitroaminostilbene-2,2-disulphonic acid are reacted in the two-phase system with a benzene solution of 19 parts .phenyl chloroformate in the presen-ceiof sodium acetate, the nitro group is reduced with iron and-hydrochloric acid and 49 parts of the 4-amino-4'-carbo-' ph'enoxyaminostilbene- 2,2-disulphonic acid so obtained acylated with 21 parts of ,phenoxyacetyl chloride. The same compound is obtained if 51.4 parts of the 4-amino-4'-phenoxyacetaminostilbene-2,2-disulphonic acid is again treated in the two-phase system with 19 parts of phenylichloroefiect on wool and cellulose fastness properties.

Example 9' 1 40 parts of 4,4-nitroaminostilbene 2;2-disulfibres with .very good phonic acid are allowed to react with 21.6 parts of p-nitrobenzoyl chloride and the reaction product reduced to the diamino compound with iron and hydrochloric acid. 48.9 parts of this compound, 4-amino-4'-(4"-aminobenzoyl) -aminosti1 phonic acid are reacted, preferably as in Example 4, with 23 parts of 3,4-dichlorophenylisocyanate in the two-phase system and the nitro compound is reduced with iron and hydrochloric acid. 56 parts of the 4-amino-4'-(3",4"-dichlorophenylureido)-stilbene-2,2'-disulphonic acid obtained are acylated with 29 parts of 3,4-dichlorophen0xyacetal chloride, isolated and purified, if necessary.

When dry, this compound is ayellowish powder whose aqueous solution is suitable for brightening cotton, staple fibre and wool. Treated cellulose fibres have excellent fastness to washing as well as good fastness properties in general Example 6 51.4 parts of 4amino-4-phenoxyacetaminostilbene-2,2'-disulphonic acid as described in Example 2 are allowed to react in aqueous solution bene-2,2-disulphonic acid are acylated with 42 parts of phenoxyacetyl chloride, preferably in the two-phase system. The product when/pure is a yellow powder suitable for the brightening of cellulose fibres and of wool.

It is of particular interest for use as an additive to soap powder and to other washing agents.

Example 10 0.01% t 0.1% of 4-phenoxyacetamino-4-phenylureido-stilbene-2,2'-disulphonic acid is added to a washing agent consisting of:

parts of soap 1 l6 parts'of soda ash and 5 parts of water glass Cotton fabric washed with this washing agent by ordinary domestic laundering methods has a very beautiful white appearance after'rinslng and drying.

according to the methods given in Examples 1-9. 'Theyall have similar valuableproperties.

$10511 HAOQ What we claim is: REFERENCES CITED A bnghtemng agent compnsmg compound The following references are of record in the of the formula file of this patent:

C Q 35 UNITED STATES PATENTS 803E 803E v so Name 1940 wherein Y stands for an acyl radical of an arylschmld oxy substituted acetic acid of the benzene FOREIGN PATENTS series, and Z stands for a member selected from Number Country Date the group consisting of lower alkyl, lower alkoxy, 534,484 Great Britain Jan 15, 1947 aryloxymethylene of the benzene series, arylamino of the benzene series and aryl of the ben- OTHER REFERENCES zene series, this compound containing not more Stobbe et a1., Ber. V. 46 (1913) pages 1226-1238, than the two sulfonic acid groups indicated in 13 pages. the above formula.

2. A brightening agent comprising a compound of the formula SOaH 3. A brightening agent comprising a compound of the formula O0 CHz-CO-NHQCH=CH NH-C0.0 01H,

4. A brightening agent comprising a compound of the formula ERNST KELLER. REINHARD ZWEIDLER. 

1. A BRIGHTENING AGENT COMPRISING A COMPOUND OF THE FORMULA 